(MONEY Magazine) – Before plunking down $29 to $75 for a game, you need to know which hardware system can play it. Most games work only on specific systems. There are three basic types: -- The conventional eight-bit systems: Nintendo's NES ($79.90), which plays 350 video games, and the Sega Master System II ($59.95), with 60 games. -- Jazzier 16-bit systems: Sega Genesis ($189.95) and the NEC TurboGrafx-16 model ($159). These offer livelier pictures and music and sound effects that make sports games in particular a lot of fun. NEC also now has an optional $399 attachment for its TurboGrafx-16 that enhances sound and visuals through compact disks. Only a handful of games are on CD so far, though, at about $62 a pop. -- Hand-held portable sets: Nintendo's monochrome Game Boy ($89.95), and the 1990 color entries with superior sound quality, Atari's Lynx ($179) and the NEC TurboExpress ($250) -- which plays the identical software as the TurboGrafx-16. If you hook on a $100 tuner, it converts to a mini-TV.